近12000年以来北京地区地球磁场变化机理探讨

摘要

距今12000年以来北京地区地球磁场长期变化由长周期(大于1000年)和短周期(约500年)两部分组成，长周期和短周期分量分别受控于漂移场和稳定场的变化. 与日本地区相比，北京地区地球磁场最显著的特征是在距今(5110—4670)±110年之间曾发生短极性漂移事件，这样的短极性地磁事件可能与地球外核流体运动的异常变化有关.%The paleomagnetic secular variation (PSV) in Beijing over the last 12000 years can be divided into long-term (＞1000 years) and short-term (500-1000 years) components. The long-term variations are mainly controlled by changes in the drifting field, while the short-term variations are most probably caused by the fluctuation of the standing field. Comparing to the PSV in Japan, a remarkable feature in Beijing is a short geomagnetic excursion occurring between (5110-4670)±110 years,which might be related with the anomaly movement of the fluid in the Earth's outer core.